Molecular Mechanisms of SERT in Platelets: Regulation of Plasma Serotonin Levels

The role of 5HT in platelet function. SERT (dark blue elongated hexagons) within the plasma membrane (light blue line) transports 5HT, which is a signal for platelet activation, from the plasma into the platelet cytoplasm. 5HT is stored within the platelet in dense granules; α-granules store proagulant molecules. Both types of granules can release their contents into the plasma under appropriate platelet stimulation. The internalization and recycling of SERT through platelet trafficking machinery provides a means of regulating 5HT uptake. (See text for details.)